Mathematica Another bug? Weird integration results.

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The discussion centers on a problem with integrating a function in Mathematica, specifically when integrating parts of the function separately versus as a whole. The user notes that integrating each piece of the function yields different results compared to integrating the entire function at once. They provide code snippets demonstrating their approach, using assumptions for the variables r and z. The results from separate integrations are compared to the result from a full integration, revealing discrepancies. Further exploration indicates that simplifying the function before integration affects the outcome, leading to different numerical results. The user seeks confirmation from others regarding this issue in Mathematica version 9.
Hepth
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I can't upload the notebook I guess, that would be a nice feature mods! (.nb extension)

But here is my code , there seems to be a problem with integrating separately and then combining.

Code:
$Assumptions = 0 < r < 1 && 0 < z < 1;
FUNCTION = Expand[-(Pi*(-1 + r)*(-12*z + r^2*z + r*(-12 + 11*z)))/(12*(r*(-1 + z) - z))];
temp1 = Table[Integrate[FUNCTION[[i]], z, Assumptions -> $Assumptions], {i, 1, Length[FUNCTION]}] // Total // Expand
temp2 = Integrate[FUNCTION, z, Assumptions -> $Assumptions] // Expand
temp1 /. {r -> 1/16., z -> 0.1}
temp2 /. {r -> 1/16., z -> 0.1}

So the problem is that if I choose each piece of the function, integrate them individually, its not the same result as if i do the whole integration.

This is on MM9 right now. Can anyone confirm this? My results are

0.297957 -0.620063 I
0.495329 -0.00321276 I
 
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Wow it really is just something with not fullsimplifying the function first :

Code:
FUNCTION = (-12*z + r^2*z + r*(-12 + 11*z))/(12*(r*(-1 + z) - z));
Integrate[   Simplify[FUNCTION,   0 < r < 1 && 0 < z < 1], z] /. {r -> 1/16, z -> 1/10} // N
Integrate[   FullSimplify[FUNCTION,   0 < r < 1 && 0 < z < 1], z] /. {r -> 1/16, z -> 1/10} // N

0.168179 -0.00109083 I

0.101165
 

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